Measuring instrument.



A. S. LANE & S.. KENLEY.

MEASURING INSTRUMENT. APPLICATION FILED JAN.2|H,1908.

Patented Nov. 10, 1908,

a. W J [W w sub ect of the Em UNITED STATES PATE OFFICE.

ARTHUR SMYTHE LANE,- or ornswrcx, AND STANLEY KENLEY, or ACTON, ENGLAND.

- MEASURING INSTRUMENT.

Specification of Letters Patent.

Patented Nov. 10, 1908.

' Application filed January as, 1903. Serial No. 41am.

LANE and STANLEY KENLEY, respectively a subset of the King of Great Britain and a eror of Germany, residing, respectively, at C- wick and Acton, both m the county ofMiddlesex, England, have 1nventednew and useful Improvements in Measuring Instruments, of which the followmg is a specification.

This invention relates to improvements in measuring instruments more especially of that class in which the object to be measured is placed between two jaws one of which is fixed and the other adjustable towards and from the object by means of a screw, the number of revolutions or travel of wh ch indicates on suitable scales or verniers the exact distance between the fixed and movable jaws at any moment, that is to say the exact space occupied by the object to be measured. Such instruments are adapted for measuring internal measurements (such as the internal diameter of a tube for example) or external measurements (such as the diameter of a shaft for example).

According to the present invention means are provided by which any inaccuracy, within certain fixed limits, of the object to be measured, is clearly and visibly indicated in a simple and direct manner.

Figure 1 of the accompanying drawings illustrates a side view of a measuring instrument with our im rovements applied thereto; Fig. 2 is a simi ar view to Fig. 1, but with the cover plate on one side of the instrument removed; Fig. 3 is a similar view of the reverse side of one end portion only of the instrument with the coverplate removed; and Fig. 4 is an elevation partly in section of the end portion only of the instrument as in Fig.

2, but drawn to a larger scale than in that figure.

parts in all the figures of the drawings.

a is the U-shaped frame of the instrument,

ing jaws, the space e between which and the jaw f is increased or diminished according to the direction of rotation of the milled head b as is well understood in connection with this class of measuring instrument Instead of the jaw f being a fixed abut- Similar letters of reference relate to like ment, as has been the case heretofore, it

forms part of a spring plunger g mounted in the head it of the instrument, as seen clearly in Fig. 4.

11 is an annular recess formed in the lunger' g, and j is the reduced tail end 0 the plunger screw-threaded to receive the screw ca k.

l is a helical compression spring surrounding the reduced portion m of the lunger g and hearing at its inner end upon the end of the plunger as shown, and at its outer end on the inner surface of the internalflange n of the head h.

o is a loose sleeve sliding in the interior of the head it and surrounding ,the sprin 1. It will be understood that the .sliding s eeveo limits the amount of movement of the plunger 9 against the action of the helical spring when the said plunger is forced to the left hand in Fig. 4, t e movement of the plunger p to the right hand in the same figure being imited by the screw cap is bearing at its inner end upon the external surface of the internal flange n.

The space in which the sleeve 0 slides may be increased or diminished by screwing the screw cap is on the tail end 7' of the plunger g, the said screw cap 7c hearing at its inner and upon the exterior surface of the internal flan e n and drawing the plunger 9 to the left and in Fig. 4 or vice versa a ainst the resistance of the spring I when regu ating the instrument. I

p isa set :or lockin screw bearing at its inner end upon the re uced endof thepiunger .g, and by which the redetermined position'of the screwed cap fc in relation to the plunger 9, that is to say the amount of movement of the sleeve 0, may be accurately set.

9 is a downwardly projecting lever lpivota ed at 1" to the frame a, as shown in fu lines in Fig. 3, and in dotted lines in 4, and having a spur or talon s which passes through a hole in the head h and enters the beforementioned annular recess i bearin against the side of such recess asseen clear y in Fig.

4, and retained in that osition by means of the spring t as shown in ig. 3. At the lower end of the lever g is a pm a which passes through a hole '1) in the frame a, and engages with the short end an of a second lever in which is pivoted at y to the frame a and extends in an upward'direction as shown in Figs. 2 and 4, its short end 'w being caused to bear against the pin it 'of the lever g by means ame a, by screws or otherwise as shown in Fig. 1.

11 order to set the index finger 5 at the'end of the lever :20 at the desired normal position in relation to the graduated segmental scale 2, the set or locking screw 1 is slackened back and the screw ca k is turned in the appropriate direction, y which the levers g and x are moved as desired throu h the spur or talon s, and when set at the esired position the screw cap 7c is locked by means of the screw p, the screw cap 7c being suitably held stationary by the flat surfaces 4.

If the milled head 6 is turned until the end surfaces of the jaws d and f make mechanical touch and the index finger 5 at the end of the lever :12 is set so that it stands at the numeralZ on the right hand side of the graduated scale 2, as in Figs. 1 and 2, the zero mark of the circumferential scale a on the inner graduated edge of the milled head I; will'stand at two dlvisions below the longitudinal base or zero line of the fixed longitudinal scale 6; and in order to make these two zero lines coincide it will be necessary to further turn the milled head 6 forward by the space of two divisions of its scale 0, thereb forcing the jaw f and plunger 12 to the le t hand in Figs. 1 and 2 against t e resistance .of the helical spring Z and moving the index finger 5 at the end of the lever a: into the zero position on the graduated segmental scale 2. v The apparatus may be employed in a variety of ways according to re uirements. In

Fig. 1,for-exam Ie, the milled sad 6 has been turned into sue a position that the reading of the rotatin circumferential scale a in relation to the ed longitudinal scale 6 indicates 350 thousandths of an inch, but the is of accurate length, the index finger 5 atthe end of the lever a; will now stand at the .zeroline of the graduated segmental scale 2, but if it is short of the required length, thesaid finger will indicatethe amount of such deficiency in one thousandths of an inch to the right hand of the zero line of that scale, or any excess of the required length to'the left of the said line. By the employment of this instrument objects may be accurately measured by sight only in a very simple and expeditious manner mstead of relying upon testing by touch as heretofore, and all risk of forcing the jaws agamst the object-to be measured is obviated within practical limits.

Claim. 4

A measuring instrument of the kind described which consists of a frame a, a jaw d with rotating head I) and circumferential scale 0, a fixed longitudinal scale 6, a jaw f with sliding plunger 9 and recess 11, a spring I, a sleeve 0, a screwed tail end 7' of plunger a screw cap is, a set or locking screw p, a spring-urged lever q with spur or talon 8 engaging wlth recess i, a pin it on lever g, a spring-urged lever x to engaging with pin a and termlnating in an index finger 5, and a scale 2, substantially as described.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

ARTHUR SMYTHE LANE. STANLEY KENLEY.

Witnesses: I F. L. RAND, R. O. WILLIAMs. 

